Though they are very good mass and force sensors, their quality factors have been somewhat modest.
thus enabling these systems to become appealing mass and force sensors, and exciting quantum systems. Why is This Discovery so Important?
This led the group to produce nanostructures that have historically been considered impossible to assemble. The widely used method of metamaterial synthesis is top-down fabrication such as electron beam
The films can also serve as supercapacitors which store energy quickly as static charge and release it in a burst.
The Rice lab built supercapacitors with the films; in tests they retained 90 percent of their capacity after 10000 charge-discharge cycles and 83 percent after 20000 cycles.
These could be fuel cells supercapacitors and batteries. And we've demonstrated two of those three are possible with this new material l
#Better bomb-sniffing technology with new detector material University of Utah engineers have developed a new type of carbon nanotube material for handheld sensors that will be quicker
plans to build a prototype handheld sensor by year's end and produce the first commercial scanners early next year, says cofounder Ling Zang, a professor of materials science and engineering and senior author of a study of the technology published online Nov 4 in the journal
and then deposit a microscopic amount on electrodes in a prototype handheld scanner that can detect toxic gases such as sarin or chlorine,
When the sensor detects molecules from an explosive, deadly gas or drugs such as methamphetamine, they alter the electrical current through the nanotube materials,
"You can apply voltage between the electrodes and monitor the current through the nanotube,"says Zang, a professor with USTAR, the Utah Science Technology and Research economic development initiative."
The technology also can be applied to existing detectors or airport scanners used to sense explosives or chemical threats.
"Unlike the today's detectors, which analyze the spectra of ionized molecules of explosives and chemicals,
which will improve the future development of chemical sensors used in chemical and engineering industries.
In an international study University of Melbourne and the National Institute of Standards and Technology in the US found that pairs of closely spaced nano particles made of gold can act as optical antennas.
This geometry now determines the efficiency nanoparticle use as a chemical sensor in sensing minute quantities of chemicals in air and water.
Chief Investigator Ken Crozier a professor of Physics and Electronic engineering at the University of Melbourne said Up until now there were two competing theories surrounding
but not so good when used in electronics that generally need to convey heat away from a source.
or even inside electronic devices to help move heat away from heat generating chips. The team next plans to work on creating models that have more detail and
Researchers combine graphene and copper in hopes of shrinking electronics More information: Thermal conductivity of Graphene Laminate Nano Lett. 2014 14 (9) pp 5155-5161.
Yet while scientists made great strides in reducing of the size of individual computer components through microelectronics,
they have been less successful at reducing the distance between transistors, the main element of our computers.
These spaces between transistors have been much more challenging and extremely expensive to miniaturize an obstacle that limits the future development of computers.
Molecular electronics, which uses molecules as building blocks for the fabrication of electronic components, was seen as the ultimate solution to the miniaturization challenge.
#Team reveals molecular structure of water at gold electrodes When a solid material is immersed in a liquid the liquid immediately next to its surface differs from that of the bulk liquid at the molecular level.
When the solid surface is charged just like an electrode in a working battery it can drive further changes in the interfacial liquid.
At an electrode surface the build up of electrical charge driven by a potential difference (or voltage) produces a strong electric field that drives molecular rearrangements in the electrolyte next to the electrode.
Berkeley Lab researchers have developed a method not only to look at the molecules next to the electrode surface
but to determine their arrangement changes depending on the voltage. With gold as a chemically inert electrode and slightly-saline water as an electrolyte Salmeron and colleagues used a new twist on x-ray absorption spectroscopy XAS) to probe the interface
and show how the interfacial molecules are arranged. XAS itself is not new. In this process a material absorbs x-ray photons at a specific rate as a function of photon energy.
The electrons arriving at the gold electrode surface can be detected as an electrical current traveling through a wire attached to it.
when studying liquids in contact with working electrodes because they carry a steady current as in batteries and other electrochemical systems.
When measuring current off the electrode it is critical to determine which part is due to the x-rays and
That's the main thing we know about the gold electrode surface from the x-ray absorption spectra:
Water next to the electrode has a different molecular structure than it would in the absence of the electrode.
This study which is reported in Science in a paper titled The structure of interfacial water on gold electrodes studied by x-ray absorption spectroscopy marks the first time that the scientific community has shown such high sensitivity in an in-situ environment under working electrode conditions s
#NIST offers electronics industry two ways to snoop on self-organizing molecules A few short years ago,
It's old news that the semiconductor industry is starting to run up against physical limits to the decades-long trend of ever-denser integrated chips with smaller and smaller feature sizes,
Just recently, Intel Corp. announced that it had in production a new generation of chips with a 14-nanometer minimum feature size.
"The issue in semiconductor lithography is not really making small featuresou can do thatut you can't pack them close together,
and in theory, you have a near-perfect pattern for lines spaced 10 to 20 nanometers apart to become, perhaps, part of a transistor array.
at individual sections of a film by doing three-dimensional tomography with a transmission electron microscope (TEM).*
That's a huge factor in the electronics industry. d
#Nanoparticle technology triples the production of biogas Researchers of the Catalan Institute of Nanoscience and Nanotechnology (ICN2), a Severo Ochoa Centre of Excellence,
and electronics Assistant professor Karton said. Ever since the discovery of graphene in 2004 scientists have been looking for potential applications in nanochemistry he said.
The global market for graphene is reported to have reached US$9 million this year with most sales concentrated in the semiconductor electronics battery energy and composites.
however because conventional metal electrode technologies are too thick(>500 nm) to be transparent to light making them incompatible with many optical approaches.
See-through sensors open new window into the brain More information: Graphene-based carbon-layered electrode array technology for neural imaging and optogenetic applications.
Nature Communications 5 Article number: 5258 DOI: 10.1038/ncomms625 5
#Materials for the next generation of electronics and photovoltaics One of the longstanding problems of working with nanomaterials substances at the molecular and atomic scale is controlling their size.
When their size changes their properties also change. This suggests that uniform control over size is critical
in order to use them reliably as components in electronics. Put another way if you don't control size you will have inhomogeneity in performance says Mark Hersam.
One property that distinguishes these materials from traditional semiconductors like silicon is that they are mechanically flexible.
That allows us to integrate electronics on flexible substrates like clothing shoes and wrist bands for real time monitoring of biomedical diagnostics and athletic performance.
These materials have the right combination of properties to realize wearable electronics. He and his colleagues also are working on energy technologies such as solar cells
and thus can be integrated with flexible electronics. They likely even will prove waterproof. It turns out that carbon nanomaterials are hydrophobic so water will roll right off of them he says.
#See-through one-atom-thick carbon electrodes powerful tool to study brain disorders Researchers from the Perelman School of medicine and School of engineering at the University of Pennsylvania and The Children's Hospital of Philadelphia have used graphene
While previous efforts have been made to construct transparent electrodes using indium tin oxide they are expensive and highly brittle making that substance ill-suited for microelectrode arrays.
so we can make very thin flexible electrodes that can hug the neural tissue Kuzum notes.
The team also notes that the single-electrode techniques used in the Nature Communications study could be adapted easily to study other larger areas of the brain with more expansive arrays.
Ertugrul Cubukcu's lab at Materials science and engineering Department helped with the graphene processing technology used in fabricating flexible transparent neural electrodes as well as performing optical and materials characterization in collaboration with Euijae Shim and Jason Reed.
#Flexible paper electrodes with ultra-high loading for lithium-sulfur batteries With the rapid development of portable electronic devices, electric automobiles,
Recently, scientists from Tsinghua University have created a freestanding carbon nanotube paper electrode with high sulfur loading for lithium-sulfur batteries.
"CNTS are one of the most efficient and effective conductive fillers for electrode. We selected short multi-walled CNTS (MWCNTS) with lengths of 10-50 m as the shortrange electrical conductive network to support sulfur,
as well as super long CNTS with lengths of 1000-2000 m from vertically aligned CNTS (VACNTS) as both long-range conductive networks and inter-penetrated binders for the hierarchical freestanding paper electrode.""
"Such sulfur electrodes with hierarchical CNT scaffolds can accommodate over 5 to 10 times the sulfur species compared with conventional electrodes on metal foil current collectors
as well as modifying precursors in the electrode, which neutralized the advantage of Li-S system in high specific capacity.
"The areal capacity can be increased further to 15.1 mah cm-2 by stacking three CNT-S paper electrodes, with an areal sulfur loading of 17.3 mg cm-2 as the cathode in a Li
This proof-of-concept experiment indicates that the rational design of the nanostructured electrode offers the possibility of the efficient use of active materials as practical loading."
"The current bottom-up electrode fabrication procedure is effective for the preparation of large-scale flexible paper electrodes with good distribution of all functional compounds,
which is also favorable for graphene, CNT-graphene, CNTMETAL oxide based flexible electrodes, "Qiang said."
"The as-obtained freestanding paper electrode is promising for the ubiquitous applications of Li-S batteries with low cost,
high energy densities for future flexible electronic devices such as smart electronics and roll up displays. y
#New self-assembly method for fabricating graphene nanoribbons First characterized in 2004 graphene is a two-dimensional material with extraordinary properties.
The thickness of just one carbon atom and hundreds of times faster at conducting heat and charge than silicon graphene is expected to revolutionize high-speed transistors in the near future.
and edge configurations scientists have theorized that nanoribbons with zigzag edges are the most magnetic making them suitable for spintronics applications.
Spintronics devices unlike conventional electronics use electrons'spins rather than their charge. But this top-down fabrication approach is not yet practical
This new method of graphene fabrication by self-assembly is a stepping stone toward the production of self-assembled graphene devices that will vastly improve the performance of data storage circuits batteries and electronics.
three-dimensional (3d) structures for applications in devices such as batteries and supercapacitors. Their study was published recently in the journal Nature Communications.
which will be highly useful as electrodes and membranes for energy generation or storage. While we have demonstrated only the construction of graphene-based structures in this study we strongly believe that the new technique will be able to serve as a general method for the assembly of a much wider range of nanomaterials concluded Franklin Kim the principal investigator of the study y
#Engineers develop prototype of low-cost disposable lung infection detector Imagine a low-cost, disposable breath analysis device that a person with cystic fibrosis could use at home
Materials scientist Regina Ragan and electrical engineer Filippo Capolino have created a nano-optical sensor that can detect trace levels of infection in a small sample of breath.
They made the sensor in the laboratory but would like to see it become commercially available.
Nanotechnologies such as this sensor depend on extremely small nanometer scale building blocks. A nanometer is about 100,000 times smaller than the width of a human hair.
#Beyond LEDS: Brighter new energy saving flat panel lights based on carbon nanotubes Even as the 2014 Nobel prize in Physics has enshrined light emitting diodes (LEDS) as the single most significant and disruptive energy-efficient lighting solution of today scientists
around the world continue unabated to search for the even-better-bulbs of tomorrow. Electronics based on carbon especially carbon nanotubes (CNTS) are emerging as successors to silicon for making semiconductor materials.
And they may enable a new generation of brighter low-power low-cost lighting devices that could challenge the dominance of light-emitting diodes (LEDS) in the future
and help meet society's ever-escalating demand for greener bulbs. Scientists from Tohoku University in Japan have developed a new type of energy-efficient flat light source based on carbon nanotubes with very low power consumption of around 0. 1 Watt for every hour's operation
about a hundred times lower than that of an LED. In the journal Review of Scientific instruments from AIP publishing the researchers detail the fabrication
and optimization of the device which is based on a phosphor screen and single-walled carbon nanotubes as electrodes in a diode structure.
Then they painted the mixture onto the positive electrode or cathode and scratched the surface with sandpaper to form a light panel capable of producing a large stable and homogenous emission current with low energy consumption.
Our simple'diode'panel could obtain high brightness efficiency of 60 Lumen per Watt which holds excellent potential for a lighting device with low power consumption said Norihiro Shimoi the lead researcher and an associate professor of environmental studies at the Tohoku University.
For instance LEDS can produce 100s Lumen per Watt and OLEDS (organic LEDS) around 40. Although the device has a diode-like structure its light-emitting system is not based on a diode system
which are made from layers of semiconductors materials that act like a cross between a conductor and an insulator the electrical properties
of which can be controlled with the addition of impurities called dopants. The new devices have luminescence systems that function more like cathode ray tubes with carbon nanotubes acting as cathodes
and an anode with the improved phosphor screen in our diode structure obtained no flicker field emission current and good brightness homogeneity Shimoi said.
The resistance of cathode electrode with highly crystalline single-walled carbon nanotube is very low. Thus the new flat-panel device has compared smaller energy loss with other current lighting devices
Now the team led by Dzurak has discovered a way to create an artificial atom qubit with a device remarkably similar to the silicon transistors used in consumer electronics known as MOSFETS.
what is modified basically a version of a normal transistor is something that almost nobody believed possible until today Morello says.
The ability to mold inorganic nanoparticles out of materials such as gold and silver in precisely designed 3-D shapes is a significant breakthrough that has the potential to advance laser technology microscopy solar cells electronics environmental testing
Such systems may one day replace the electronic circuits we are using today
#Researchers develop green tea-based'missiles'to kill cancer cells more effectively Green tea has long been known for its antioxidant, anticancer, antiaging and antimicrobial properties.
The same prototype also crams 1900 emitters onto a chip that's only a centimeter square quadrupling the array size and emitter density of even the best of its predecessors.
or the height of deposits must be consistent across an entire chip. To control the nanotubes'growth the researchers first cover the emitter array with an ultrathin catalyst film
The new structures can lead to sensors and chips for future devices like smartphones computers and medical equipment.
#New absorber will lead to better biosensors Biological sensors or biosensors are like technological canaries in the coalmine.
An optical biosensor works by absorbing a specific bandwidth of light and shifting the spectrum
Currently plasmonic absorbers used in biosensors have a resonant bandwidth of 50 nanometers said Koray Aydin assistant professor of electrical engineering and computer science at Northwestern University's Mccormick School of engineering and Applied science.
It is significantly challenging to design absorbers with narrower bandwidths. Aydin and his team have created a new nanostructure that absorbs a very narrow spectrum of light#having a bandwidth of just 12 nanometers.
This ultranarrow band absorber can be used for a variety of applications including better biosensors. We believe that our unique narrowband absorber design will enhance the sensitivity of biosensors Aydin said.
#All directions are created not equal for nanoscale heat sources Thermal considerations are rapidly becoming one of the most serious design constraints in microelectronics, especially on submicron scale lengths.
The transistor spacing in RF devices is rapidly approaching length-scales where theory based on the diffusion of heat won't be valid,
#A new dimension for integrated circuits: 3-D nanomagnetic logic Electrical engineers at the Technical University Munich (TUM) have demonstrated a new kind of building block for digital integrated circuits.
Their experiments show that future computer chips could be based on three-dimensional arrangements of nanometer scale magnets instead of transistors.
As the main enabling technology of the semiconductor industry CMOS fabrication of silicon chips approaches fundamental limits, the TUM researchers and collaborators at the University of Notre dame are exploring"magnetic computing"as an alternative.
They report their latest results in the journal Nanotechnology. In a 3d stack of nanomagnets, the researchers have implemented a so-called majority logic gate
which could serve as a programmable switch in a digital circuit. They explain the underlying principle with a simple illustration:
Think of the way ordinary bar magnets behave when you bring them near each other, with opposite poles attracting
and synchronization in magnetic circuits, similar to latches in electrical integrated circuits.""All players in the semiconductor business benefit from one industry-wide cooperative effort:
developing long-range"roadmaps"that chart potential pathways to common technological goals. In the most recent issue of the International Technology Roadmap for Semiconductors, nanomagnetic logic is given serious consideration among a diverse zoo of"emerging research devices."
"Magnetic circuits are nonvolatile, meaning they don't need power to remember what state they are in.
The potential to pack more gates onto a chip is especially important. Nanomagnetic logic can allow very dense packing, for several reasons.
The most basic building blocks, the individual nanomagnets, are comparable in size to individual transistors. Furthermore, where transistors require contacts and wiring,
nanomagnets operate purely with coupling fields. Also, in building CMOS and nanomagnetic devices that have the same function for example
a so-called full-adder it can take fewer magnets than transistors to get the job done.
leader of the TUM research group within the Institute for Technical Electronics.""However, there might be applications where the nonvolatile,
#Blades of grass inspire advance in organic solar cells Using a biomimicking analog of one of nature's most efficient light-harvesting structures blades of grass an international research team led by Alejandro Briseno of the University of Massachusetts Amherst
has taken a major step in developing long-sought polymer architecture to boost power-conversion efficiency of light to electricity for use in electronic devices.
and vertical transistors he adds. Briseno explains: For decades scientists and engineers have placed great effort in trying to control the morphology of p-n junction interfaces in organic solar cells.
and packing at electrode surfaces the team combined knowledge about graphene and organic crystals. Though it was difficult Briseno says they managed to get the necessary compounds to stack like coins.
and we didn't even realize until we imaged the surface of the substrate with a scanning electron microscope.
We envision that our nanopillar solar cells will appeal to low-end energy applications such as gadgets toys sensors and short lifetime disposable devices s
To see as much detail as possible the team decided to use a set of electron detectors to collect electrons in a wide range of scattering angles an arrangement that gave them plenty of structural information to assemble a clear picture of the battery's interior down to the nanoscale level.
and allowing for more affordable flexible displays. The majority of today's touchscreen devices such as tablets and smartphones are made using indium tin oxide (ITO)
Using a simple scalable and inexpensive method the researchers produced hybrid electrodes the building blocks of touchscreen technology from silver nanowires and graphene.
and could replace existing touchscreen technologies in electronic devices. Even though this material is cheaper and easier to produce it does not compromise on performance.
Conductive nanofiber networks for flexible unbreakable and transparent electrode e
#Harnessing an unusual'valley'quantum property of electrons Yoshihiro Iwasa and colleagues from the RIKEN Center for Emergent Matter Science the University of Tokyo and Hiroshima University have discovered that ultrathin films of a semiconducting material have properties that form the basis for a new kind of low-power electronics
termed'valleytronics'.'Electronic components store transmit and process information using the electrical charge of an electron.
The use of charge however requires physically moving electrons from one point to another which can consume a great deal of energy particularly in computing applications.
Semiconductors and insulators derive their electrical properties from a gap between the highest band occupied by electrons known as the valence band
#Solar cell compound probed under pressure Gallium arsenide Gaas a semiconductor composed of gallium and arsenic is well known to have physical properties that promise practical applications.
and optoelectronics in many of the same applications that silicon is used commonly. But the natural semiconducting ability of Gaas requires some tuning
The specific energy required to make this jump to the conducting state is defined as the band gap.
Fine-tuning of this band gap has the potential to improve gallium arsenide's commercial potential. There are different methods available to engineer slight tweaks to the band gap.
Goncharov's team focused on the novel application of very high pressure which can cause a compound to undergo electronic changes that can alter the electron-carrier properties of materials.
It had already been demonstrated on nanowires made from one crystalline form of gallium arsenide the cubic so-called zincblende structure that the band gap widens under pressure.
The team subjected wurtzite gallium arsenide to up to about 227000 times normal atmospheric pressure (23 gigapascals) in diamond anvil cells.
They discovered the band gap that the electrons need to leap across to also widened although not as much as in the case of the zincblende crystal nanowires.
Significantly they discovered that around 207000 times normal atmospheric pressure (21 gigapascals) the wurtzite gallium arsenide nanowires underwent a structural change that induced a new phase the so-called orthorhombic one
but resulting in significant differences in the size of the'band gap'between the two crystalline structures of gallium arsenide suggests that both types of Gaas structures could theoretically be incorporated into a single device
We believe these findings will stimulate further research into gallium arsenide for both basic scientific and practical purposes s
Although the researchers did not have precise control over the nanowire morphology they did observe that higher concentrations of H2o2 led to thicker nanowires.
As the researchers conclude in their report These results of Si nanowire arrays are believed to be useful for future optoelectronic and photovoltaic applications.
Mixing silicon with other materials improves the diversity of nanoscale electronic devices More information: Oda K. Nanai Y. Sato T. Kimura S. & Okuno T. Correlation between photoluminescence and structure in silicon nanowires fabricated by metal-assisted etching.
Silicon nanoparticles such as those in RM 8027 are being studied as alternative semiconductor materials for next-generation photovoltaic solar cells and solid-state lighting,
#Self-organized indium arsenide quantum dots for solar cells Kouichi Yamaguchi is recognized internationally for his pioneering research on the fabrication and applications of'semiconducting quantum dots'(QDS.
and photovoltaic devices arise from the unique optoelectronic properties of the QDS when irradiated with light or under external electromagnetic fields.
#Enabling bendable optoelectronics devices: Gallium nitride micro-rods grown on graphene substrates Bendy light-emitting diode (LED) displays
and solar cells crafted with inorganic compound semiconductor micro-rods are moving one step closer to reality thanks to graphene and the work of a team of researchers in Korea.
Currently most flexible electronics and optoelectronics devices are fabricated using organic materials. But inorganic compound semiconductors such as gallium nitride (Gan) can provide plenty of advantages over organic materials for use in these devices#including superior optical electrical and mechanical properties.
One major obstacle that has prevented so far the use of inorganic compound semiconductors in these types of applications was the difficulty of growing them on flexible substrates.
In the journal APL Materials from AIP Publishing a team of Seoul National University (SNU) researchers led by Professor Gyu-Chul Yi describes their work growing Gan micro-rods
on graphene to create transferrable LEDS and enable the fabrication of bendable and stretchable devices.
Gan microstructures and nanostructures are garnering attention within the research community as light-emitting devices because of their variable-color light emission
To create the actual Gan microstructure LEDS on the graphene substrates the team uses a catalyst-free metal-organic chemical vapor deposition (MOCVD) process they developed back in 2002.
and reliability of Gan micro-rod LEDS fabricated on graphene to the test they found that the resulting flexible LEDS showed intense electroluminescence (EL)
This represents a tremendous breakthrough for next-generation electronics and optoelectronics devices#enabling the use of large-scale and low-cost manufacturing processes.
By taking advantage of larger-sized graphene films hybrid heterostructures can be used to fabricate various electronics
and optoelectronics devices such as flexible and wearable LED displays for commercial use said Yi. Explore further:
Scientists grow a new challenger to graphene More information: Growth and characterizations of Gan micro-rods on graphene films for flexible light-emitting diodes by Kunook Chung Hyeonjun Beak Youngbin Tchoe Hongseok Oh Hyobin Yoo Miyoung Kim and Gyu
-Chul Yi APL Materials September 23 2014: scitation. aip. org/content/aip/#/9/10.1063/1. 489478 1
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